JP2002533166A - Storage / filter system and method of use - Google Patents

Abstract

SUMMARY OF THE INVENTION Embodiments of the present invention are provided with a reservoir and filter system that receives a fluid and removes impurities from the fluid. The system includes a housing defining a plurality of cavities having at least one unfiltered fluid inlet in fluid communication with the first cavity and at least one filtrate outlet in fluid communication with the second cavity. This embodiment includes a filter member to separate the cavities. Additionally, a filtration trap is positioned to receive and filter fluid as it enters the first cavity and to minimize clogging of the filter member. A preferred embodiment includes a coarse filter shroud that provides a funnel shape at the opening of the cup-shaped trap. In one embodiment, at least one gas outlet that can be modified to be connected to a vacuum source is associated with the second cavity. In a further embodiment, a method is provided for removing impurities from blood in an extracorporeal circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[Industrial applications]

The present invention generally relates to a system for receiving, storing, and filtering fluids for further filtrate processing. In particular, the invention relates to the processing of blood or other applied biological fluids.

[0002]

[Background Art]

A notable application of reservoir and filter systems is in blood and other applied biological fluid processing. For example, drawing blood from a surgical site can be a high-throughput operation if a large amount of blood is generated quickly, that is, an operation in which a large amount of blood is processed within a certain period of time.

[0003] Many state-of-the-art reservoir and filter systems are designed such that an essentially flat filter is placed to divide the reservoir into compartments. The first part is intended to contain the unfiltered fluid obtained from the source liquid, i.e. the unfiltered fluid, while the other part holds the filtrate. In common practice, the filter is oriented such that the filter surface is perpendicular to gravity and the portions are laterally adjacent to one another. By applying a partial vacuum, the fluid is forced into the reservoir and is sent through a flat filter after sufficient fluid has been collected to create a head pressure sufficient to force the fluid through the filter. In high-throughput applications, such filters will necessarily become clogged, as safety mechanisms for removing impurities from filters during operation are limited or absent. Clogging usually occurs at the bottom of the filter due to gravity, reducing the effective active filtration area over time and clogging a volume of unfiltered fluid. Over time, filters will become more and more prone to clogging at higher levels, and more unfiltered fluid will stagnate. The ability to efficiently filter fluids will weaken over time.

[0004]

According to a first embodiment of the present invention, there is provided a reservoir and filter system for receiving a fluid and removing impurities from the fluid. The embodiment includes a housing including at least two cavities. Further, the housing has at least one unfiltered fluid inlet in fluid communication with the first cavity and at least one filtrate outlet in fluid communication with the second cavity. The filter member retains some of the impurities while allowing impeded fluid communication between the first and second cavities. According to this embodiment, a filtration trap is also included. The trap may be cup-shaped with an opening, a bottom and sides defining a chamber. Such a filter cup is positioned in the first cavity, the opening of which is proximal to the inlet, and is oriented to receive fluid into the chamber and collect impurities at the bottom while simultaneously passing the chamber and through the side. Fluid communication between the first cavities is enabled. Furthermore, the fact that the depth of the filter cup is less than the height of the first cavity,
Fluid from the chamber is allowed to flow into the first cavity. In other embodiments, a coarse filter shroud further arranged to provide a funnel shape at the trap opening is further included. In a preferred embodiment, the second cavity further includes at least one gas outlet connected to a vacuum source.

[0005] Reservoir and filter systems may be used in a range of potential applications. In a special embodiment, it is provided that it is used as part of an extracorporeal blood treatment device. It is desirable to remove blood and by-products generated during certain surgical procedures from the surgical site quickly. The system facilitates the collection of unfiltered blood. Unwanted blood impurities, residues and clots are then filtered, and the resulting filtrate can be further processed. In an embodiment of the system, the housing is made of a transparent material that is compatible with blood.

In accordance with another embodiment of the present invention, a method for removing impurities from blood in an extracorporeal circuit comprises providing a reservoir and filter system in a circuit between an unfiltered blood source and a location maintained at reduced pressure. Positioning, introducing blood into the circuit, and collecting the filtrate. The reservoir and filter system includes a housing, a filter member, and a filtration trap having the above features.

[0007]

[Detailed description of special embodiment]

The various embodiments of the reservoir and filter system described herein address many of the shortcomings inherent in previous designs. For example, premature plugging of a single filter system results in reduced filtrate throughput (throughput in time). This plugging reduces the effectiveness of the partial vacuum or other differential pressurization mechanism in driving unfiltered fluid from the fluid source and driving the filtrate to its destination.

FIG. 1 illustrates a system according to one embodiment of the present invention, the coupling of a reservoir and filter system 100 with other components that may be in fluid communication. As an example of how the system 100 may be used in an extracorporeal blood circuit, the system 100 is shown in FIG. Unfiltered fluid obtained from fluid source 10 is directed into reservoir 1 through unfiltered fluid inlet 12. The fluid source 10 for a particular application may be in communication with a surgical location where blood, debris (residue) or other fluid is generated. During a surgical procedure, it may be crucial that blood is quickly removed from the surgical site as soon as blood, in addition to other fluids and debris, develops. The rate and volume of blood generated depends on the particular surgical procedure. System 100 is designed to efficiently collect and filter fluid from a range of throughput processes. Vacuum source 15 is connected to reservoir 1 by vacuum line 14. The example diagram illustrates a situation in which a vacuum may be useful to blood processing device 1000 in addition to driving fluid through system 100. A differential pressure is set to cause the flow of fluid from the fluid source 10 to flow into the reservoir 1. In blood treatment apparatus 1000, a partial vacuum may be used to draw filtrate from filtrate outlet 13 of the system into inlet 16 of the centrifuge rotor. In this embodiment, the reservoir 1 is divided into an inlet cavity 2 and an adjacent outlet cavity 3. Shown is a filter member 17 arranged to physically separate the inlet cavity 2 from the outlet cavity 3. Filter member 17 may have one or more filtration layers. According to a preferred embodiment, the filter member 17 comprises at least one foam rubber (cellular rubber)
And a mesh sieve. The mesh sieve is arranged adjacent to the outlet cavity 3. The foam rubber layer does not clog as quickly as the mesh sieve. That is, the foam rubber layer allows fluid to pass around physical obstacles (such as debris or impurities) as opposed to a mesh sieve. If clogged, the screen sieve then leads to inefficient filtration and fluid throughput.

Fluid is first obtained from a fluid source 10 using differential pressurization techniques (such as the generation of a partial vacuum).
It is drawn into the inlet cavity 2 through the inlet line 11 and the unfiltered fluid inlet 12. As the fluid volume (and consequently the fluid height) in the inlet cavity 2 increases, a head pressure is established until a breakthrough pressure is reached, at which point the fluid is driven through the filter member 17 leaving a residue behind and the filtration Liquid enters the outlet cavity 3. The filtrate then flows out of the outlet cavity 3 through the filtrate outlet 13 and in this embodiment,
It is further processed by the device 1000. Partial vacuum or other differential pressurization (in a preferred embodiment, generated by or in connection with apparatus 1000) is used to draw filtrate from outlet cavity 3. Outlet line 18 directs fluid into centrifuge inlet 16 of apparatus 1000 for separating various fluid components for future use.

FIG. 2 is a side view of the inlet cavity 2 of the reservoir and filter system 100 according to a preferred embodiment of the present invention. The unfiltered fluid is driven directly through the inlet 12 into the filtration trap 20 located in the inlet cavity 2. In this embodiment, the filtration trap has a cup shape. Arrow 21 indicates the direction of fluid flow. The filter cup 20 is oriented to receive incoming unfiltered fluid into the chamber as long as the chamber does not overflow and until it overflows. Chamber fluid level 22 is indicated for the condition of partially filled filter cup 20. As schematically represented by the cup support 23, the filter cup 20 is supported so that it is kept in place regardless of the vacuum applied to the reservoir 1, while at the same time receiving and filtering fluid. . Although not shown, a strategy is provided in the inlet cavity 2 and the outlet cavity 3 as well as connected with the cup support 23 to reinforce the collapse of the whole reservoir 1 due to the vacuum applied during operation. Constitutive supports that can be arranged in an efficient manner are useful. Fragment 2
4 remains in the filter cup 20 and accumulates near the cup bottom 25. Thus, the chamber of the filter cup 20 is clogged with debris 24 near the cup bottom 25, but at the same time it is possible to filter the fluid and to allow the filtrate to flow into the rest of the inlet cavity 2 through the side of the cup 20. enable. The filtration arrow 28 illustrates the direction of filtrate flow from inside the filter cup 20 to the outside. The inlet cavity fluid level 26 is shown.
Under normal flow conditions (no overflow of the cup), no debris 24 is obtained that undesirably clogs the filter member 17 (shown schematically). However, in the overflow condition, some fluid will flow directly from the inlet 12 into the inlet cavity 2 without passing through the filter cup 20. In this situation, some debris 24 will reach the filter member 17 and will help undesirably clog the filter member 17. The overflow condition indicates that the proportion (velocity) of the incoming unfiltered fluid is higher than the filter cup 20.
Is designed to occur only when the rate of filtration made by the filter is exceeded or when the filter cup 20 is filled with debris. In this state, the system 100
It will work similarly to the operation of the prior art single filter system. Filtration trap 2
Zero can be made with a foam rubber material chosen based on the required filtration rate for a given process. The foam rubber material could be similar in properties to those used in the filtration layer of the filter member 17. As in the prior art system, any unfiltered fluid within the remainder of the inlet cavity 2 would be filtered by the filter member 17 and only the filtrate could flow into the outlet cavity 3. However, according to embodiments of the present invention, in system 100, the majority of the fluid reaching filter member 17 will already be filtrate. The filtrate will flow rapidly into the outlet cavity 3 and will then go to its destination.

FIG. 3 is a side view of the outlet cavity 3 of the reservoir and filter system 100 according to an embodiment of the present invention. An outlet cavity fluid level 30 is shown. The partially cut-away view shows the vacuum line 14 coupled to the cap 31. Microorganisms or other barrier materials designed to isolate the contents of the reservoir 1 from the vacuum line 14 and the outside environment may be located within the cap 31 of the preferred embodiment. In the embodiment shown, the mesh sieve 32 portion of the filter member 17 (shown schematically) acts as a filtration layer and provides the necessary lateral support.

In this embodiment, a hollow area 70 is provided in the outlet cavity 3. As long as the reservoir 1 is kept vertical during operation, the filtrate flowing through the filter member 17
Will gather in area 70. When a partial vacuum, which creates a different pressure, is applied to the filtrate outlet 13, the filtrate flows from the area 70 shown below on the pipe 34 and upwards out of the outlet cavity 3 through the pipe 34 and the filtrate outlet 13, as indicated by arrow 13 Spills in the direction of. According to the illustrated embodiment, a float tube 35 is positioned above the cutout region 70 with an essentially vertically oriented orientation. The float tube 35 is a cap 3
1 has an upper float tube end 300 that is arranged to mate with a hole 301 provided therein. The float 36 is mounted vertically in the float tube 35 at or near the exit cavity fluid level 30 due to its buoyancy. The float 36 is sized to be accommodated (seated) in the bore 301 when the exit cavity fluid level 30 is such that the entire exit cavity 3 is filled with fluid. When the float 36 is received in the hole 301, the communication between the cap 31 and thus the vacuum source 15 and the outlet cavity 3 via the vacuum line 14 is removed. In such a situation, the partial vacuum created through the vacuum line 14 is blocked, and no additional fluid is driven into the system 100 until the level 30 drops and the float 36 is disengaged from the hole 301. In a preferred embodiment, the partial vacuum used to draw fluid from outlet cavity 3 to device 1000 may be further controlled so that if level 30 is below a defined threshold height, it will not be activated.

FIG. 4 is a side view of a filtration trap 20 mounted according to one embodiment of the present invention. According to this preferred embodiment, the coarse filter shroud 40 is arranged to provide a funnel shape at the opening of the filtration trap 20 (shown as having a cup shape) for receiving unfiltered fluid coming from the inlet 12. The shroud 40 is made of a much coarser filter material than that of the filter cup 20 or the filter member 17. The coarse filtration material is passed through both the opening 41 cut into the shroud 40 and, to a lesser extent, the coarse filtration material that constitutes the shroud 40, to allow unfiltered fluid and associated impurities and debris to fall into the cup 20. Should be able to flow into The shape of the shroud 40 is such that the majority of the unfiltered fluid is directed first to the bottom of the filter cup 20. Since the partial vacuum tends to spray the unfiltered fluid, the shroud 40 keeps the unfiltered fluid from being blown directly onto the side wall of the cup 20. In addition, some impurities and debris are blocked by shroud 40 as unfiltered liquid is directed into filter cup 20.

FIG. 5 shows that continuous fluid flow from the unfiltered fluid inlet 12 flows from the inlet cavity 2 into the filter cup 20 via the directional arrow 51 into the arrows 52, 53, 54, 55, 56, 5, 5.
Exiting through the filtrate outlet 13 continuously in the directions 7 and 58 is illustrated. Since most of the fluid is filtered by the filter cup 20, the filter member 17
There is no tendency to clog.

FIG. 6 is a side view of the inlet cavity 2 of the reservoir and filter system 100 according to another embodiment of the present invention. In this embodiment, the inlet cavity 2 is divided by the separator 60 into a first sub-cavity 61 and a second sub-cavity 62. Separator 60 may be made of a solid material or a foam rubber material. The foam rubber material may be made of a similar quality as that used for the filtration trap 20. The first subcavity 61 does not receive fluid until the inlet subcavity fluid level 66 reaches and exceeds the top 63 of the solid material separator 60. If the separator 60 is a foam baffle, some filtered fluid at the lower subcavity fluid level may escape to the first subcavity. By providing a sub-cavity, less fluid is required to generate sufficient head pressure to pierce the filter member 17. In this embodiment, the increased filtrate throughput into the outlet cavity 3 is facilitated by configuring the filter member 17 in the area adjacent to the filtration trap 20 with only the mesh sieve portion 32 (rather than multiple layers). Is done. This area, including the single mesh sieve 32, can be further reduced to an area located at a height less than or equal to the top 63. Components (not shown) that are incorporated to stabilize the system 100 may instead be used economically as the boundaries of the filter member 17 having only a single mesh sieve. The above embodiments are believed to hasten the initial flow of fluid to the outlet cavity 3 in situations where rapid priming of the system 100 is desired. In particular, the related device 100
This is important if an earlier start of processing by zero is required. FIG. 7 illustrates firstly how the filtrate enters the outlet cavity 3 through a rectangular area 71 containing a single mesh screen 32 as the filter member 17. The fluid flow arrows further indicate how level 30 increases.

According to another embodiment of the present invention, reservoir system 100 is made of a transparent material to facilitate viewing of fluid flow and fluid levels. Methyl methacrylic acid acrylonitrile butadiene styrene (MABS) polymer is one such material that has been successfully advertised. The reservoir 1 is generally rectangular in shape,
It is not limited by such an example. Each component should be included in the inlet cavity 2 and the outlet cavity 3 for various purposes. One such purpose is to provide the required stiffness for structural stability under operating pressure. Another purpose is to additionally serve as support 23 for such components, filtration trap 20, tube 34 and filter member 17. The efficient use of such a member as a convenient boundary for adjusting the configuration of the filter member 17 has been described above. The component can also be used to create a sub-cavity in the entrance cavity 2. System 10
0 is economically designed to be disposable after a single use.

FIG. 8 illustrates another embodiment of the invention using a generally rectangular reservoir 1. In this embodiment, inlet 12 and trap 20 are at an angle with respect to reservoir 1. The trap 20 occupies a larger portion of the entrance cavity 82 and debris is "bottom" 81
Rather, they gather at the trapping surface 80. The bottom 81 also serves as a filter member 84 that separates the inlet cavity 82 from the outlet cavity 83. The trap surface 80 has
Acting as a "shelf", the remainder of the entrance cavity 82 (external trap 20) is located below the trap 20, rather than beside it. The trapping surface 80 is made of a foam material similar to that used in the above embodiment.

FIG. 9 illustrates yet another embodiment of the present invention. Here, the entrance cavity 92 is
During the initial phase of the filtration, the fluid height per unit of fluid volume is contoured to be higher than for the rectangular configuration. The increase in fluid height is proportional to the increase in pressure driving fluid through filter member 17 to outlet cavity 93. this is,
This can be important if a quicker start of processing by the associated device 1000 is required.

The system 100 is suitable for use in an extracorporeal blood circuit. In this application, impurities from the surgical site are removed from the blood. All materials used in the system construction are blood compatible according to industry standards and regulations. Blood draining from the postoperative wound drain is also received and filtered through an inlet (separate from inlet 12). In such an embodiment, the reservoir 1 may be further partitioned to separate such unfiltered wound drain blood and the resulting filtrate from that blood obtained from the surgical site.

In still other embodiments, a suitable light deflecting material may be used to surround the float tube 35 to provide appropriate contrast for viewing the float 36. In that case, some type of sensor known in the art may be used to detect the float 36 position within the float tube 35 to inform about the fluid level of the reservoir 1.
Further, the system 100 may be used to continue collecting blood from a post-operative wound drain as previously described. The sensor can also be used to monitor drain blood volume during processing. If such an amount exceeds a predetermined threshold, system 100 may include an alert to alert personnel.

[0021] Also disclosed herein is a method of removing impurities from blood in an extracorporeal circuit, including placing the system 100 in the circuit, introducing blood into the circuit, and collecting filtrate. .

Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that various modifications may be made without departing from the spirit and scope of the invention as set forth in the appended claims. Will be.

[Brief description of the drawings]

FIG. 1 is an isometric view of a reservoir and filter system according to one embodiment of the invention, illustrating the coupling of other components, such as a blood processing device, in fluid communication with the system.

FIG. 2 is a side view of a first cavity of a reservoir and filter system according to one embodiment of the present invention.

FIG. 3 is a side view of a second cavity of the reservoir and filter system according to one embodiment of the present invention.

FIG. 4 is a side view of a filtration trap exemplified by one embodiment of the present invention.

FIG. 5 is a block diagram illustrating the flow of fluid into and out of the reservoir through the filtration trap and members from the inlet, according to one embodiment of the present invention.

FIG. 6 is a side view of a first cavity of a reservoir and filter system according to another embodiment of the present invention.

FIG. 7 is a side view of the second cavity according to the embodiment of FIG. 6;

FIG. 8 is a cross-sectional view of a reservoir and filter system according to a further embodiment of the present invention.

FIG. 9 is a cross-sectional view of another embodiment of a reservoir and filter system.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B01D 29/90 B01D 29/04 510Z 29/92 530A 29/42 501A 510 (72) Inventors Headley, Thomas Dee United States of America, Massachusetts 02481, Wellgate, Westgate Road 83 (72) Inventor Stroll, Clare El United States of America, Massachusetts 02056, Norfolk, Winston Road 3 (72) Inventor Martin, Clifford United States of America, Massachusetts State 02053, Medway, Castle Road 5F Term (Reference) 4C077 AA12 BB02 CC03 CC06 DD12 EE01 KK11 LL12 LL13 MM10 NN20

Claims (19)

[Claims] 1. A reservoir and filter system for receiving and removing impurities from a fluid, the housing and the housing defining a plurality of cavities, the at least one unfiltered fluid inlet in fluid communication with the first cavity. A housing having at least one filtrate outlet in fluid communication with the second cavity; and a filter member disposed within the housing to separate the first cavity from the second cavity. A filter member that retains a portion while permitting impeded fluid communication between the first and second cavities; and a filter trap disposed within the first cavity proximate the at least one unfiltered fluid inlet. A filtration trap oriented to receive fluid and to permit fluid outflow from the trap into the first cavity. Filter system. 2. A reservoir and filter system for receiving a fluid and removing impurities from the fluid, the reservoir and filter system defining a plurality of cavities, the at least one housing being in fluid communication with the first cavity. A housing having an unfiltered fluid inlet and at least one filtrate outlet in fluid communication with the second cavity; and a filter member disposed within the housing to separate the first cavity from the second cavity. A filter member that retains some of the impurities while allowing impeded fluid communication between the first and second cavities; and a filter cup having an opening, a bottom, and a side surface to define a chamber of a certain depth. And
The opening is located in the first cavity proximal to the at least one unfiltered fluid inlet and is oriented to receive fluid into the chamber, and directs fluid outflow from the chamber into the first cavity. A filter cup wherein said depth is less than said height to allow for said reservoir and filter system. 3. The system of claim 2, further comprising a coarse filter shroud arranged to provide a funnel shape at said opening. 4. The system of claim 2, wherein said fluid is extracorporeal blood. 5. The system of claim 4, wherein the housing is made of a transparent material that is compatible with blood. 6. The system of claim 2, wherein said second cavity further comprises at least one gas outlet adapted to be connected to a vacuum source. 7. The system of claim 6, wherein said fluid is extracorporeal blood. 8. The system of claim 2, wherein the filter cup is capable of collecting impurities at the bottom while allowing fluid communication between the chamber and the first cavity through the side. 9. The filter member includes a plurality of filtration layers, and the unfiltered fluid comprises a second filtration layer.
9. The system of claim 8, wherein the filtration layer is provided such that all of the layers must pass through before reaching the cavity. 10. The system of claim 9, wherein one of said plurality of filtration layers is a mesh sieve. 11. The apparatus further comprises a separator arranged to divide the first cavity into two sub-cavities, wherein the filter cup is provided in the first sub-cavity, wherein the separator includes the chamber and the second sub-cavity. 9. The system of claim 8, wherein fluid communication between the sub-cavities is limited. 12. The apparatus of claim 12, further comprising a separator disposed to divide the first cavity into two sub-cavities, wherein the filter cup is provided in the first sub-cavity, wherein the filter cup is provided in the first sub-cavity. 11. The system of claim 10, wherein fluid communication between the sub-cavities is limited. 13. The system of claim 11, wherein one of said plurality of filtration layers is a mesh sieve. 14. The system of claim 11, wherein a portion of said filter member adjacent said first sub-cavity is a single filtration layer. 15. The system of claim 14, wherein said single filtration layer is a mesh sieve. 16. A method for removing impurities from blood in an extracorporeal circuit, comprising placing a reservoir and filter system in the circuit between a source of unfiltered blood and a location maintained at reduced pressure, the method comprising: A filter and filter system comprising: a housing defining a plurality of cavities, the housing having at least one unfiltered fluid inlet in fluid communication with the first cavity and at least one filtrate outlet in fluid communication with the second cavity; A filter member disposed within the housing to separate the first cavity from the second cavity, the filter member retaining some of the impurities while simultaneously impeding fluid communication between the first and second cavities. A filter member disposed in the second cavity proximate the at least one unfiltered fluid inlet to receive fluid and flow fluid from the trap into the first cavity. And a filtering trap oriented as to permit to introduce the blood into the circuit consists of collecting the filtrate from the filtrate outlet, the blood impurity removal process in the extracorporeal circuit. 17. A method of removing impurities from blood in an extracorporeal circuit, comprising placing a reservoir and filter system in the circuit between a source of unfiltered blood and a location maintained at reduced pressure, the method comprising: The filter and filter system is a height housing defining a plurality of cavities, wherein at least one unfiltered fluid inlet in fluid communication with the first cavity and at least one unfiltered fluid inlet in fluid communication with the second cavity.
A housing having two filtrate outlets; and a filter member disposed within the housing to separate the first cavity from the second cavity, the filter member retaining a portion of the impurities while simultaneously retaining the first and the second. A filter member that allows impeded fluid communication between the two cavities; and a filter cup having an opening, a bottom, and a side surface to define a chamber of a depth, wherein the opening is the at least one unfiltered fluid. Positioned in the first cavity proximal to the inlet and oriented to receive fluid into the chamber, the depth is adjusted to allow fluid to flow out of the chamber into the first cavity. A filter cup adapted to be less than a height, introducing blood into the circuit and collecting the filtrate from the filtrate outlet, the method for removing blood impurities in an extracorporeal circuit. 18. The method of claim 17, wherein the filter cup allows impurity collection at the bottom while allowing fluid communication between the chamber and the first cavity through the side. 19. The method of claim 17, further comprising a coarse filter shroud arranged to provide a funnel shape at said opening.